A photovoltaic panel or a solar panel is an interconnected assembly of solar cells and is the basic component of a photovoltaic system.
Manufacturers of photovoltaic panels specify electrical characteristics which may include maximum rated power, open circuit voltage, short circuit current, maximum power voltage, maximum power current, temperature coefficients and insulation resistance.
Insulation resistance testing may be carried out by shorting a positive terminal and a negative terminal of a solar panel, and then by applying a predetermined voltage between the live electrical section and the outer housing, backside, the frame, and ground terminals. Wet insulation testing of photovoltaic panels may include performing resistance measurement on the insulation of a photovoltaic panel immersed in a liquid solution bath. The insulation resistance test and wet insulation test verifies that the solar panel or the solar cell array has insulation high enough to reduce the possibility of fire and electrocution hazards.
An increase in maximum system voltage may place an extra burden on photovoltaic manufacturers with regard to insulation resistance. Further, photovoltaic modules can exhibit performance degradation in the field when subjected to high voltages at elevated temperatures in a humid climate. Given that increased system voltage may place an extra burden on panel manufacturers to provide better insulation, and given that increased maximum system voltage may be a cause of performance degradation of photovoltaic modules, there is a need for and it would be advantageous to have circuitry integrated with a photovoltaic panel which provides features to allow more photovoltaic panels to be wired serially in a string without needing higher insulation resistance of the photovoltaic panel and lower operating voltage operation of photovoltaic panels so as to increase long term lifetime of a photovoltaic system.